From mboxrd@z Thu Jan  1 00:00:00 1970
Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail
From: Michael Heerdegen <michael_heerdegen@web.de>
Newsgroups: gmane.emacs.help
Subject: Re: filemananger for emacs with meta information about a file without
 opening it
Date: Thu, 03 Nov 2022 12:15:58 +0100
Message-ID: <87leos9tld.fsf@web.de>
References: <87k04fzpkj.fsf@mat.ucm.es>
 <Y2NkbTyB7SHpVDnB@protected.localdomain> <Y2N0QMNe2SogXyAe@tuxteam.de>
 <CAP_d_8X4nFoPn8D4EjPoPVNvvx6v_Y_Niw_3m-rO=4SaNq3GRQ@mail.gmail.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 8bit
Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214";
	logging-data="26324"; mail-complaints-to="usenet@ciao.gmane.io"
User-Agent: Gnus/5.13 (Gnus v5.13)
To: help-gnu-emacs@gnu.org
Cancel-Lock: sha1:S5NxnWEmGIVFUnOP0JWtMakMfIk=
Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Thu Nov 03 12:16:41 2022
Return-path: <help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org>
Envelope-to: geh-help-gnu-emacs@m.gmane-mx.org
Original-Received: from lists.gnu.org ([209.51.188.17])
	by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256)
	(Exim 4.92)
	(envelope-from <help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org>)
	id 1oqYDA-0006dy-Bo
	for geh-help-gnu-emacs@m.gmane-mx.org; Thu, 03 Nov 2022 12:16:40 +0100
Original-Received: from localhost ([::1] helo=lists1p.gnu.org)
	by lists.gnu.org with esmtp (Exim 4.90_1)
	(envelope-from <help-gnu-emacs-bounces@gnu.org>)
	id 1oqYCm-00083N-5a; Thu, 03 Nov 2022 07:16:17 -0400
Original-Received: from eggs.gnu.org ([2001:470:142:3::10])
 by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256)
 (Exim 4.90_1) (envelope-from <geh-help-gnu-emacs@m.gmane-mx.org>)
 id 1oqYCc-00081l-CT
 for help-gnu-emacs@gnu.org; Thu, 03 Nov 2022 07:16:06 -0400
Original-Received: from ciao.gmane.io ([116.202.254.214])
 by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256)
 (Exim 4.90_1) (envelope-from <geh-help-gnu-emacs@m.gmane-mx.org>)
 id 1oqYCa-0003Yl-WA
 for help-gnu-emacs@gnu.org; Thu, 03 Nov 2022 07:16:06 -0400
Original-Received: from list by ciao.gmane.io with local (Exim 4.92)
 (envelope-from <geh-help-gnu-emacs@m.gmane-mx.org>)
 id 1oqYCY-0005iF-8a
 for help-gnu-emacs@gnu.org; Thu, 03 Nov 2022 12:16:02 +0100
X-Injected-Via-Gmane: http://gmane.org/
Received-SPF: pass client-ip=116.202.254.214;
 envelope-from=geh-help-gnu-emacs@m.gmane-mx.org; helo=ciao.gmane.io
X-Spam_score_int: -15
X-Spam_score: -1.6
X-Spam_bar: -
X-Spam_report: (-1.6 / 5.0 requ) BAYES_00=-1.9,
 FREEMAIL_FORGED_FROMDOMAIN=0.001, FREEMAIL_FROM=0.001,
 HEADER_FROM_DIFFERENT_DOMAINS=0.25, SPF_HELO_NONE=0.001,
 SPF_PASS=-0.001 autolearn=no autolearn_force=no
X-Spam_action: no action
X-BeenThere: help-gnu-emacs@gnu.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Users list for the GNU Emacs text editor <help-gnu-emacs.gnu.org>
List-Unsubscribe: <https://lists.gnu.org/mailman/options/help-gnu-emacs>,
 <mailto:help-gnu-emacs-request@gnu.org?subject=unsubscribe>
List-Archive: <https://lists.gnu.org/archive/html/help-gnu-emacs>
List-Post: <mailto:help-gnu-emacs@gnu.org>
List-Help: <mailto:help-gnu-emacs-request@gnu.org?subject=help>
List-Subscribe: <https://lists.gnu.org/mailman/listinfo/help-gnu-emacs>,
 <mailto:help-gnu-emacs-request@gnu.org?subject=subscribe>
Original-Sender: "help-gnu-emacs" <help-gnu-emacs-bounces@gnu.org>
Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org
Xref: news.gmane.io gmane.emacs.help:140611
Archived-At: <http://permalink.gmane.org/gmane.emacs.help/140611>

Yuri Khan <yuri.v.khan@gmail.com> writes:

> > How do you find out a picture's resolution without opening the file?
>
> Nohow. The opening is just not perceived by the user. The pedantic
> description would probably be “without visiting in a buffer and
> without starting an associated interactive application”.

I read it as "without reading the complete file contents from disk".

To get some metadata about images one has to look at the contents but
the first N bytes may be enough with an appropriate small N.

Michael.